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Classification of all things

  1. Aug 24, 2013 #1
    Is there a classification of all things? This question actually arises from the 20 Q game. If things are categorized and arranged as a tree, it would be very easy.
    I don't think there exist such a categorization (who has the time!) but still is it possible?

    You could start with natural and human-made things and then go on further.
  2. jcsd
  3. Aug 24, 2013 #2
    consult set theory
  4. Aug 24, 2013 #3
    Of course everything can be put into classes.......I if something is discovered that doesn't fit, we just make a new class for it!
  5. Aug 24, 2013 #4
    I don't understand how set theory is related to my question.
    Yes of course. I was looking if it is possible to intuitively list out all the categories.
    Something like this - Well, we need food, shelter, things for our comfort. Now food can be plants or animals .... and so on.
  6. Aug 24, 2013 #5


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    There are many taxonomies, or taxonomic schemes that have been created for things.


    But no practical taxonomy explicitly contains everything. I suppose it would be like trying to draw every detail of a fractal. And you can count on some things being more ambiguous to classify than others, for any given taxonomic scheme. I imagine cultural difference, language semantics and connotations complicate the process. (It doesn't keep people from trying though).
  7. Aug 26, 2013 #6
    I love when things are systematic like the way we have classified each fundamental particle, elements etc.
    But I suppose there are just too many things, too many combinations to systematically categorize everything.

    Thank You anyways!
  8. Aug 26, 2013 #7


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    I think in the 20Q thread there was also a link to an online version. If you have played it you will already have noticed some ambiguities.
    For example, I was thinking of the sun, and then it asks questions like "is it shiny", "is it used for entertainment" to which I don't really know the answer. And I answered "Yes" to "Can it be painted" while apparently it thinks not. In that case, I guess you will have answered your own question.
  9. Aug 26, 2013 #8
    I think its possible, but rather than a tree it would form a web, where single node can have many connections.
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